Portal

I've beaten Portal before a couple times. Currently, in the flinging section of test chamber 18 Chell is flying backward FOR NO REASON and landing in the goo. Only once on this run have I made it to the second flinging platform.

I do need to clean my keyboard. That aside, it's a case of sometimes doing exactly the same thing can have different results. Flinging "stairway" has never give me this much trouble before. Sometimes Chell seems to be going straight up until the peak of the fling, which is when she starts drifting backward.

I still can't figure out why I sometimes end up landing on the floor when I have a portal above me and one under me either. Let's see if verifying the game cache does anything, because I certainly didn't have the sudden excess motion from flinging in any other chamber.